If you saw a demon you would turn instantly religious because of the sheer frightening spectacle before you and that's the last thing generally that a demon wants to do is turn people religious. An enemy is more powerful if they remain in stealth mode. Tactical warfare

The fact of the matter: The reason why you do not see demons is because God is still in control of everything, that is why you do not see demons, but you see evil in this world, that is Satan at work with his fallen angels.

There is no convincing evidence that any supernatural creatures exist, just stories, and words are cheap. People sometimes report waking up and seeing a 'ghost' or 'demon' hovering over their beds; these are hypnagogic hallucinations and nothing supernatural.
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